Mise en ligne effectuee par
Molécules et Composites pour l’Optique (MCO)
Molécules et Composites pour l’Optique
Isabelle Malfant, Responsable d’équipe, Pr, UPS
isabelle.malfant chez lcc-toulouse.fr
+33 5 61 33 31 01
Bonneval, Mdc, UPS
benedicte.debonneval chez lcc-toulouse.fr
+33 5 61 33 31 52
isabelle.sasaki chez lcc-toulouse.fr
+33 5 61 33 31 88
, Technicienne chimiste
marine.tasse chez lcc-toulouse.fr
+33 5 61 33 31 88
Non Permanents :
Joëlle Akl, doctorante MESR
+33 5 61 33 31 12
Daniel Hernandez, doctorant, bourse Mexique
CV Daniel HERNÁNDEZ MALDONADO au format PDF
+33 5 61 33 31 12
Chelmia Billot, stagiaire M2R chimie, Toulouse
Anciens non permanents :
Liste détaillée au format PDF
The design and characterization of new molecular photoactive materials are at the heart of our group. The materials currently under consideration have mainly interesting properties for optical storage (photochromic), photovoltaics (electron donors and acceptors) and the nonlinear optical switching. Our studies are located on the border of two key themes : photonics and organic electronics. New developments are also dealing with photodynamic therapy.
Keywords : Organic Photovoltaïcs - Ni bis-dithiolene complexes - Donor small molecules - Non linear Optics - Molecular Switching - Photochromism - Ruthenium complexes - Nitrosyl ligand - Optical data storage - Photodynamic Therapy - Two Photon Absorption
Organic Materials for Photovoltaics
Organic photovoltaics (OPVs) promise a remarkable cost reduction of photovoltaic (PV) energy, if large improvements of efficiency and lifetime could be achieved. OPV cells are based on Donor/Acceptor molecules. Our previous investigations concerned materials leading to columnar liquid crystal (CLC) structures :
Optical microscopy for CLC complex, in transmission with slightly uncrossed polarizers, observed at room temperature
These molecules absorb strongly up until near-infrared (NIR). We have been working on nickel bis-dithiolene (Ni-bdt) complexes as new OPV acceptors and we succeeded, by using appropriate ligands, in structuring some of them in hexagonal columnar phases.
X-Ray diffraction pattern (left) of a single domain of (Ni-bdt) which exhibits Bragg peaks characteristic of hexagonal columnar mesophase (right)
We now turn our activities through the design and synthesis of innovative acceptors and low band gap new donor small molecules. We combine experiment (synthesis of materials) and theory (theoretical calculation) in order to optimize the materials. Thanks to new collaborations established with LAAS and LAPLACE Laboratories, we perform thin films engineering and optical/electrical characterizations to set up new photovoltaic cells.
Ruthenium Nitrosyl Systems
The ruthenium nitrosyl complexes offer a large variety of physical-chemical properties. In particular, they are of great interest in optical data storage as well as for therapeutic applications.
Photoinduced Linkage Isomerisation
These complexes are characterized by the existence of long-lived metastable states (t > 107s) for specific irradiation at a temperature close to ambient temperature. The different states have different Ru-NO conformations which are responsible for a high change in the refractive index, a very important parameter for holographic data storage. [RuCl(py)4(NO)](PF6)2.1/2H2O (py=pyridine) complex studied previously in the group is high of interest because of its complete molecular photoswitching at the solid state.
Our results show that such photochromic composites could be obtained when the complexes are embedded in polymer or silica matrices.
Xerogel of [RuCl(py)4(NO)](PF6)2.1/2H2O, french patent n° 0900126/ extension PCT
The ruthenium nitrosyl complexes have also the property to release NO upon irradiation which is very important for therapeutic applications. Indeed, the NO molecule (Nobel Price of medecine in 1998) is involved in several physiological processes (blood pressure regulation, neurotransmission, cancer cells treatment,….). Nevertheless, NO has also the ability to induce apoptosis (cell death) in healthy cells. Development of site-specific NO donors is therefore beneficial in selective killing malignant cells. Phototriggered NO release provides one such strategy. Our strategy is based on the use of appropriate two photon absorption (TPA) antenna.
Ru-NO + H2O → Ru-H2O + NO
P, K. Mascharack ACS Med. Chem. Lett., 2010, 1(4), 180-183
Multi-functional materials and molecular switches have long been a traditional interest of our research. Along this line, the possibility to switch the NLO response of a molecule in an hybrid material by mean of any additional function (e.g. magnetic, conducting or photochromic properties) is investigated. Our expertise is based on computational chemistry, which has become an important tool for providing the efficient guidelines required by synthetic chemistry and physics, to target the microscopic origin of the NLO effects. Among various possibilities, switches can be obtained by :
- Optical effect through the total NLO extinction obtained after Ru-NO → Ru-ON isomerization in specific molecules selected by computational methods.
- Magnetic effect through a spin crossover phenomenon, in Iron(II) metal complexes, like in the [Fe(Tren)]2+ system shown below, where the magnetic (cM) vs. NLO response (IHRS) correlation is clearly established.
The [Fe(Tren)]2+ cation subjected to a spin crossover phenomenon between 200 and 300 K
These investigations are based on a fruitful network of collaborations (Bordeaux, Valence, Kiev, Mexico).
“Magnetism and Molecular Nonlinear Optical Second-Order Response Meet in
a Spin Crossover Complex”
S. Bonhommeau, P.G. Lacroix, D. Talaga, A. Bousseksou, M. Seredyuk, I.O. Fritsky, V. Rodriguez
J. Phys. Chem. C 2012, 116, 11251-11255.
Influence on the Photochromic Response of a Series of
Ruthenium Mononitrosyl Complexes”
B. Cormary, S. Ladeira, K. Jacob, P.G. Lacroix, T. Woike, D. Schaniel, I. Malfant
Inorg. Chem. 2012, 51(14), 7492-7501.
"Towards Bi-functional Materials with
conducting, photochromic and spin crossover
L. Valade, I. Malfant, C. Faulmann
L. Ouahab,. (ed.) Handbook of Multifunctional Molecular Materials, Pan Stanford Publishing, Singapore (in press).
“Synthesis, X-ray crystal structures, optical properties and modelling data of neutral bis(1,2-dithiolene) nickel complexes of the “non-cyclic SR” family”
Thanh-Tuan Bui , Minh Ha Vuong, Bénédicte Garreau-de Bonneval , Fabienne Alary, Jacob Kane, Carine Duhayon , Alix Sournia-Saquet and Kathleen I. Moineau-Chane-Ching
New J. Chem., 2012, 36, 2033-2041
Discotic nickel bisdithiolene
complexes : synthesis, optoelectrochemical and mesomorphic properties
Bui T.-T., Thiebaut O., Grelet E., Achard M.-F., Garreau-de Bonneval B., Moineau-Chane Ching K. I.
Eur. J. of Inorg. Chem, 2011, 17, 2635-2676
and Tetracarboxylic Imides and Esters :
Synthesis, Mesophase Stabilisation
and Observation of Charge-Transfer Interactions between Electron-Donating and
Kelber J., Achard M.-F., Garreau-de Bonneval B., Bock H.
Chem. Eur. J., 2011, 17 (29), 8145-8155
Synthesis, Crystal Structures, and Solid State
Quadratic Nonlinear Optical Properties of a Series of Stilbazolium
Cations Combined with Gold Cyanide Counter-Ion
Lacroix P. G., Munoz M. C., Belén Gaspar A., Real J. A., Bonhommeau S., Rodriguez V., Nakatani K.
J. Mater. Chem. 2011, 21, 15940-15949
The three-dimensional intermolecular network formed
via water molecules in trans-bis(nitrito-kN)tetrakis(pyridine-kN)ruthenium(II)
Buron-Le Cointe M., Cormary B., Toupet L., Malfant I.
Acta Cryst., 2011, C67, m375-m377.